How to get and use filename and linenumber inside _crtsetallochook?

Question

0.00/5 (No votes)

See more:

C++

int _cdecl customallochook (int type, void *pdata, size_t size, int use, long request, const unsigned char *file, int line)
{
//how to use *file and line here???
}

Posted 20-Feb-12 18:40pm

Member 8576081

Updated 20-Feb-12 18:45pm

v3

Add a Solution

Comments

Mohibur Rashid 21-Feb-12 3:51am

I am confused with your question, what do you mean by file name and line number?

Stefan_Lang 21-Feb-12 5:15am

What do you mean by that question? the parameters are passed to that function, so what is not clear about getting them? And how should we know how you intend to use them? We can't possibly help if you don't tell us what you want.

Member 8576081 22-Feb-12 1:25am

I am sorry I should have mentioned it a bit more clearly. I got my answer..Thanx anyways ! :)
Cheers!!

3 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

nv3 · Answer 1 · 2012-02-21T02:34:00

This is a hook function as it is used by _CrtSetAllocHook of the C runtime system. When you compile your allocation with _DEBUG, these parameters will contain the file name and line number on which the allocation originated from.

You might want to use them for tracking down memory leaks. MFC implements a leak detection mechanism on this basis and your own hook function might want to do something similar. That is why these things are passed. If you don't need them in your hook function, just ignore them.

Abhi Lahare · Answer 2 · 2012-02-21T09:43:00

Solution 2

Check this[^] for some pre-defined macros.

HTH
Abhi

Posted 21-Feb-12 9:43am

Abhi Lahare

Member 8576081 · Answer 3 · 2012-02-21T19:23:00

The hook receives the file name and line number only if the source file
that called 'new' or malloc was set up to use the debug versions of
'operator new' and malloc and pass them this information.

This can be done in the following way:

1) Usually in the precompiled header file:

XML

#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h>
#define DEBUG_NEW new(_NORMAL_BLOCK, THIS_FILE, __LINE__)

2) At the beginning of every source file with memory allocations:

XML

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

@nv3 - I guess you mean this right? Even after doing this I am not able to recieve the filename and linenumber in the parameters. Can you please help me with this compilation under _DEBUG thing in detail. You are right i need it for memory leaks.

How to get and use filename and linenumber inside _crtsetallochook?

3 solutions

Solution 1

Solution 2

Solution 3

Add your solution here

Preview 0